A paper sheet conveying apparatus is currently known which is equipped with a separating means including a conveyer belt, a drive roller rotating in one direction at all times, and two separator roller disposed between the drive roller and the conveyer belt so as to come into engagement with one of the drive roller and the conveyer belt exclusively with a predetermined gap from the other. However, this conventional apparatus was not equipped with any means for easily setting the predetermined gap externally. Further, as shown in FIGS. 3 and 5, the two separator rollers include a pair of rollers 2, 3 individually rotatably mounted on a common axis 1 in association with a pair of laterally spaced conveyer belts A, B, and the rollers 2, 3 have not only their inner sides 2b, 3b but also their outer sides 2a, 3a engageable with the drive roller 4.
The predetermined gap is generally very small and is usually defined to be larger than the thickness of a single paper sheet and smaller than the total thickness of two paper sheets. In the absence of any means for externally adjusting such a very small gap, the separating ability would be reduced so that when an accident, such as double-sheet conveying, occurs, an adequate action cannot be achieved quickly.
Given that the two separator rollers 2, 3 are rotatable independently from one another and that the outer contact wheels 2a, 3a engageable with the drive roller 4 are added to convey the entire width of a paper sheet, if a paper sheet M with a folded corner e as shown in FIG. 4 is inserted, one separator roller 2 will come into contact with the drive roller 4 to rotate so as to push the paper sheet back to the upstream side U as shown in FIG. 5 while the other separator roller 3 will not come into contact with the drive roller 4 so it will continue rotating so as to move the paper sheet toward the downstream side D. This causes the paper sheet M to skew and, if the worst happens, to become jammed.